Illustrates the use of chi square to compare 2 groups
(males vs. females) on a dichotomous response variable (presence or absence
of a brain tumor). See (1) the first sentence in the final paragraph of
the "Methodology" section and (2) the fifth sentence in the
third paragraph of "Results." Chi square was also used to compare
2 age groups in terms of the same response variable.

Illustrates the use of a chi square test to compare
2 groups on a categorical (and dichotomous) response variable. Also illustrates
the use of Yates' correction-for-continuity. (See the sixth paragraph
of "Methods" and the second, fourth, and fifth paragraphs of
"Results.")

In this study, chi-square tests were conducted to
investigate the demographic characteristics of participants and to compare
the study's experimental and control groups on 2 criterion variables of
interest. These tests are discussed in the second and next-to-last paragraphs
of the "Results" section, respectively.